U.S. patent number 6,540,792 [Application Number 09/541,799] was granted by the patent office on 2003-04-01 for cellulose fiber-containing structure.
This patent grant is currently assigned to Toray Industries, Inc.. Invention is credited to Hidenobu Honda, Atsushi Horiuchi, Masaki Ishii, Naoaki Ito, Akira Nagahara, Yukikazu Nanri, Katsuya Okajima, Kouichi Saito.
United States Patent |
6,540,792 |
Ishii , et al. |
April 1, 2003 |
Cellulose fiber-containing structure
Abstract
A fiber structure comprising cellulose fibers crosslinked by
using a crosslinking agent and synthetic fibers, characterized in
that the crosslinking index represented by the following formula of
the cellulose fibers is in a range of 1 to 4, and that the
synthetic fibers contain an antimicrobial agent having an inorganic
value/organic value ratio of 0.3 to 1.4. This structure has
antimicrobial property excellent in industrial washing durability
and also has shape stability such as crease resistance and
shrinkage resistance. where A is the coefficient of moisture
absorption of the fiber structure after crosslinking in an
atmosphere of 30.degree. C. and 90% RH (%), and B is the
coefficient of moisture absorption of the fiber structure after
crosslinking in an atmosphere of 20.degree. C. and 65% RH (%).
Inventors: |
Ishii; Masaki (Shiga,
JP), Horiuchi; Atsushi (Gifu, JP), Okajima;
Katsuya (Penang, MY), Nagahara; Akira (Osaka,
JP), Ito; Naoaki (Shiga, JP), Honda;
Hidenobu (Shiga, JP), Saito; Kouichi (Shiga,
JP), Nanri; Yukikazu (Shiga, JP) |
Assignee: |
Toray Industries, Inc.
(JP)
|
Family
ID: |
27310852 |
Appl.
No.: |
09/541,799 |
Filed: |
April 3, 2000 |
Foreign Application Priority Data
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|
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|
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Apr 14, 1999 [JP] |
|
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11-106854 |
Jul 6, 1999 [JP] |
|
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11-191402 |
Sep 27, 1999 [JP] |
|
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11-271886 |
|
Current U.S.
Class: |
8/115.51;
427/2.31; 427/389.9; 427/392; 8/116.1 |
Current CPC
Class: |
D06M
11/36 (20130101); D06M 11/46 (20130101); D06M
11/79 (20130101); D06M 13/355 (20130101); D06M
13/432 (20130101); D06M 15/277 (20130101); D06M
15/3566 (20130101); D06M 15/423 (20130101); D06M
15/507 (20130101); D06M 15/53 (20130101); D06M
15/564 (20130101); D06M 15/59 (20130101); D06M
15/61 (20130101); D06M 15/6436 (20130101); D06M
15/647 (20130101); D06M 16/00 (20130101) |
Current International
Class: |
D06M
15/356 (20060101); D06M 15/53 (20060101); D06M
15/643 (20060101); D06M 15/423 (20060101); D06M
15/507 (20060101); D06M 15/59 (20060101); D06M
15/61 (20060101); D06M 15/277 (20060101); D06M
15/564 (20060101); D06M 15/647 (20060101); D06M
16/00 (20060101); D06M 15/21 (20060101); D06M
15/37 (20060101); D06M 11/46 (20060101); D06M
13/432 (20060101); D06M 11/79 (20060101); D06M
11/36 (20060101); D06M 13/355 (20060101); D06M
13/00 (20060101); D06M 11/00 (20060101); D06Q
001/02 () |
Field of
Search: |
;8/115.51,116.1
;427/2.31,389.9,392 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0 952 248 |
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Oct 1999 |
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EP |
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1 024 642 |
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Mar 1966 |
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GB |
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2000-080566 |
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Mar 2000 |
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JP |
|
2000-080571 |
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Mar 2000 |
|
JP |
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WO 98 10648 |
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Mar 1998 |
|
WO |
|
Other References
Database WPI Section CH, Week 198705, Derwent Publications, Ltd.,
London, GB; Dec. 12, 1986; abstract. .
Patent Abstracts of Japan; vol. 014, No. 020 (C-676), Jan. 17,
1990; and JP 01 262944 (Nippon Shokubai Kagaku Kogyo Co. Ltd.) Oct.
19, 1989; abstract..
|
Primary Examiner: Gupta; Yogendra N.
Assistant Examiner: Hamlin; D G
Attorney, Agent or Firm: Schnader Harrison Segal & Lewis
LLP
Claims
What is claimed is:
1. A cellulose fibers-containing structure comprising a) cellulose
fibers crosslinked by using a crosslinking agent and b) synthetic
fibers, wherein the crosslinking index represented by formula (1)
of the cellulose fibers is in a range of 1 to 4, and the synthetic
fibers contain c) an antimicrobial agent having an inorganic
value/organic value ratio of 0.3 to 1.4,
where A is the coefficient of moisture absorption of the fiber
structure after crosslinking in an atmosphere of 30.degree. C. and
90% RH (%), and B is the coefficient of moisture absorption of the
fiber structure after crosslinking in an atmosphere of 20.degree.
C. and 65% RH (%), wherein the antimicrobial agent is at least one
pyridine based antimicrobial agent selected from the group
consisting of 2-chloro-6-trichloro-methylpyridine,
2-chloro-4-trichloromethyl-6-methoxypyridine,
2-chloro-4-trichloro-methyl-6-(2-furyl-methoxy)pyridine,
di(4-chlorophenyl)pyridylmethanol,
2,3,5-trichloro-4-(n-propylsulfonyl)pyridine,
2-pyridylthiol-1-oxide zinc and di(2-pyridylthiol-1-oxide).
2. A cellulose fibers-containing structure, according to claim 1,
wherein the molecular weight of the antimicrobial agent is 200 to
700.
3. A cellulose fibers-containing structure, according to claim 1,
wherein the average particle size of the antimicrobial agent is 2
.mu.m or less.
4. A cellulose fibers-containing structure, according to claim 1,
wherein the pyridine based antimicrobial agent is
2-pyridylthiol-1-oxide zinc.
5. A cellulose fibers-containing structure, according to claim 1,
wherein the antimicrobial agent adheres to or is exhausted into the
synthetic fibers.
6. A cellulose fibers-containing structure, according to claim 1,
which contains the cellulose fibers by 10 to 90 wt % based on the
total weight of the fibers.
7. A cellulose fibers-containing structure, according to claim 1,
wherein the crosslinking agent is combined with cellulose and the
microbicidal activity value (Standard Test Method: JIS L 1902) of
the structure after industrial washing is larger than 0.
8. A cellulose fibers-containing structure, according to claim 1,
wherein the synthetic fibers are made of a polyester.
9. A cellulose fibers-containing structure, according to claim 1,
which further contains a silicone based softening agent mainly
composed of an organopolysiloxane containing both amino groups and
polyoxyalkyl groups in one molecule and a polyethylene polyamine
higher fatty acid type amide compound containing an amine or at
least one group capable of reacting with a hydroxyl group.
10. A cellulose fibers-containing structure, according to claim 9,
wherein the polyethylene polyamine higher fatty acid type amide
compound is obtained by letting a polyethylene polyamine and a
higher fatty acid and at least one selected from lower dicarboxylic
acids, cyclic acid anhydrides, lower diglycidyl ethers and
diisocyanates react with each other.
11. A cellulose fibers-containing structure, according to claim 9,
which contains said silicone based softening agent by 0.06 to 1.0
wt % based on the weight of the fibers.
12. A cellulose fibers-containing structure, according to claim 1,
which further contains a hydrophilic polyester resin mainly
composed of a polyalkylene glycol-polyester block copolymer.
13. A cellulose fibers-containing structure, according to claim 9,
wherein the polyalkylene glycol-polyester block copolymer is
contained by 0.03 to 1.0 wt % based on the weight of the
fibers.
14. A cellulose fibers-containing structure, according to claim 1,
wherein a vinylsulfonic acid polymer is fixed on the surface of the
fiber structure by 1 to 20%.
15. A cellulose fibers-containing structure, according to claim 1,
wherein the cellulose fibers are pre-treated by high pressure water
vapor.
16. A cellulose fibers-containing structure, according to claim 15,
wherein the high pressure water vapor is high pressure saturated
water vapor of 120 to 200.degree. C.
17. A cellulose fibers-containing structure comprising a) cellulose
fibers crosslinked by using a crosslinking agent and b) synthetic
fibers, wherein the crosslinking index represented by formula (1)
of the cellulose fibers is in a range of 1 to 4, and the synthetic
fibers contain c) an antimicrobial agent having an inorganic
value/organic value ratio of 0.3 to 1.4,
where A is the coefficient of moisture absorption of the fiber
structure after crosslinking in an atmosphere of 30.degree. C. and
90% RH (%), and B is the coefficient of moisture absorption of the
fiber structure after crosslinking in an atmosphere of 20.degree.
C. and 65% RH (%), wherein the crosslinking agent is a
nitrogen-containing polyfunctional compound represented by the
following general formula (1): ##STR3##
wherein R.sub.1 and R.sub.2 denote, respectively independently,
--H, alkyl group with 1 to 4 carbon atoms or --CH.sub.2 OR.sub.7,
R.sub.3, R.sub.4, R.sub.5 and R.sub.6 denote, respectively
independently, --H or OR.sub.8, and R.sub.7 and R.sub.8 denote,
respectively independently, --H or alkyl group with 1 to 4 carbon
atoms.
18. A cellulose fibers-containing structure comprising a) cellulose
fibers crosslinked by using a crosslinking agent and b) synthetic
fibers, wherein the crosslinking index represented by formula (1)
of the cellulose fibers is in a range of 1 to 4, and the synthetic
fibers contain c) an antimicrobial agent having an inorganic
value/organic value ratio of 0.3 to 1.4,
where A is the coefficient of moisture absorption of the fiber
structure after crosslinking in an atmosphere of 30.degree. C. and
90% RH (%), and B is the coefficient of moisture absorption of the
fiber structure after crosslinking in an atmosphere of 20.degree.
C. and 65% RH (%), wherein a vinylsulfonic acid polymer is fixed on
the surface of the fiber structure by 1 to 20%, and wherein the
vinylsulfonic acid polymer is obtained from at least one monomer
selected from the group consisting of
2-acrylamido-2-methylpropanesulfonic acid, styrenesulfonic acid,
isoprenesulfonic acid, allylsulfonic acid and methallylsulfonic
acid.
19. A cellulose fibers-containing structure comprising a) cellulose
fibers crosslinked by using a crosslinking agent and b) synthetic
fibers, wherein the crosslinking index represented by formula (1)
of the cellulose fibers is in a range of 1 to 4, and the synthetic
fibers contain c) an antimicrobial agent having an inorganic
value/organic value ratio of 0.3 to 1.4,
where A is the coefficient of moisture absorption of the fiber
structure after crosslinking in an atmosphere of 30.degree. C. and
90% RH (%), and B is the coefficient of moisture absorption of the
fiber structure after crosslinking in an atmosphere of 20.degree.
C. and 65% RH (%), wherein a polyfluoroalkyl group-containing
acrylic copolymer, aminosilicone resin, and aminoplast resin and/or
polyfunctional block isocyanate group-containing urethane resin are
deposited on the surface of the fiber structure.
20. A cellulose fibers-containing structure comprising a) cellulose
fibers crosslinked by using a crosslinking agent and b) synthetic
fibers, wherein the crosslinking index represented by formula (1)
of the cellulose fibers is in a range of 1 to 4, and the synthetic
fibers contain c) an antimicrobial agent having an inorganic
value/organic value ratio of 0.3 to 1.4,
Crosslinking index=A-B (1)
where A is the coefficient of moisture absorption of the fiber
structure after crosslinking in an atmosphere of 30.degree. C. and
90% RH (%), and B is the coefficient of moisture absorption of the
fiber structure after crosslinking in an atmosphere of 20.degree.
C. and 65% RH (%), and a photocatalyst semiconductor and a binder
on the surface.
21. A cellulose fibers-containing structure, according to claim 20,
wherein the photocatalyst semiconductor is a compound oxide of
titanium and silicon.
22. A cellulose fibers-containing structure, according to claim 20,
wherein the binder is at least one binder selected from alkyl
silicate resins, silicone resins and fluorine resins.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a cellulose fibers-containing
structure having shape stability and antimicrobial property
excellent in industrial washing durability.
2. Description of Related Arts
Antimicrobial fiber structures are widely used in various clothes,
interlinings, linings, bedclothes, interior products, etc.
Especially in recent years, the intra-hospital infection by
Methicillin Resistant Staphylococcus Aureus (MRSA) poses a problem,
and as a countermeasure, white overalls, covers, sheets, curtains,
etc. are desired to be antibacterial against MRSA.
However, since materials used in this area are frequently
industrially washed usually at 60 to 85.degree. C., few
conventional techniques can provide those having sufficient
durability. Furthermore, if those materials contain cellulose
fibers, they have a problem that the shape stability becomes poor
after washing.
As conventional antimicrobial treatment, it has mainly been
practiced to knead an inorganic antimicrobial agent containing
silver, copper or zinc, etc. into synthetic fibers in the stage of
spinning as described in Japanese Patent Laid-Open (Kokai) No.
Hei9-273073, or to spray or pad an organic antimicrobial agent
containing a quaternary ammonium salt, etc. as described in
Japanese Patent Laid-Open (Kokai) No. Hei4-11076. The former
technique is excellent in view of washing durability, but does not
allow fabrics such as woven fabrics and knitted fabrics to be
treated. Furthermore, since the antimicrobial agent is precipitated
as crystals on the die face in the stage of spinning, there is a
problem that yarn breaking occurs often. On the other hand, the
latter technique has an advantage that fabrics can be treated to be
antimicrobial, but is inferior in view of washing durability of
antimicrobial property.
Furthermore, in the applications as described above, fabrics with
high cellulose fiber contents are preferably used since they have
high water absorbability and are agreeable to the touch, but on the
other hand, they have such disadvantages that they are likely to be
creased and shrunken by washing compared to synthetic fiber
structures and that it is difficult to let them have antimicrobial
property durable against industrial washing. These disadvantages
are desired to be overcome.
SUMMARY OF THE INVENTION
The object of this invention is to provide a cellulose
fibers-containing structure having antimicrobial property excellent
in industrial washing durability, and also having shape stability
such as crease resistance and shrinkage resistance.
The constitution of this invention is as follows.
A fiber structure comprising cellulose fibers crosslinked by using
a crosslinking agent and synthetic fibers, characterized in that
the crosslinking index represented by the following formula of the
cellulose fibers is in a range of 1 to 4, and that the synthetic
fibers contain an antimicrobial agent having an inorganic
value/organic value ratio of 0.3 to 1.4.
where A is the coefficient of moisture absorption of the fiber
structure after crosslinking in an atmosphere of 30.degree. C. and
90% RH (%), and B is the coefficient of moisture absorption of the
fiber structure after crosslinking in an atmosphere of 20.degree.
C. and 65% RH (%).
Furthermore, it is preferable that the cellulose fibers are
crosslinked and modified by using a specific nitrogen-containing
polyfunctional compound, and that the synthetic fibers have a
pyridine based antimicrobial agent fixed and exhausted into the
fibers.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The cellulose fibers-containing structure referred to in this
invention can be not only a fabric but also a band, string, thread,
etc. respectively formed by fibers. It can have any structure and
shape, but a fabric, i.e., a woven fabric, knitted fabric or
nonwoven fabric respectively containing cellulose fibers is
preferable.
The cellulose fibers in this invetnion include natural cellulose
fibers such as cotton, hemp and pulp, regenerated cellulose fibers
such as viscose rayon, etc.
In this invention, the cellulose fibers are crosslinked and
modified by a crosslinking agent. The crosslinking agent refers to
a compound which reacts with the hydroxyl groups in the cellulose
molecules constituting the cellulose fibers, particularly the
hydroxyl groups in an amorphous region causing creasing and
shrinkage at the time of washing, for forming a crosslinked
structure across and in the cellulose molecules. The crosslinking
agents which can be used include formaldehyde,
dimethylolethyleneurea, dimethyloltriazine, dimethyloluron,
dimethylolglyoxalmonouren, dimethylopropyleneurea, cellulose
reactive resins obtained by methoxylating or ethoxylating some or
all of the methylol groups of these compounds, polycarboxylic
acids, isocyanates, etc. Among these crosslinking agents, for
efficiently and effectively crosslinking and modifying cellulose
fibers, formaldehyde or a nitrogen-containing polyfunctional
compound represented by the following general formula (I) can be
preferably used. ##STR1##
where R.sub.1 and R.sub.2 denote, respectively independently, --H,
alkyl group with 1 to 4 carbon atoms or CH.sub.2 OR.sub.7 ;
R.sub.3, R.sub.4, R.sub.5 and R.sub.6 denote, respectively
independently, --H or --OR.sub.8 ; and R.sub.7 and R.sub.8 denote,
respectively independently, --H or alkyl group with 1 to 4 carbon
atoms.
As for the modification degree of cellulose fibers, the
crosslinking index defined by the following formula must be in a
range of 1 to 4. A preferable range is 2 to 3.5. The crosslinking
index is calculated by subtracting the value of the coefficient of
moisture absorption of the crosslinked and modified cellulose
fibers in an atmosphere of 20.degree. C. and 65% RH from the value
of the coefficient of absorption in an atmosphere of 30.degree. C.
and 90% RH, and it is an index for knowing how far the cellulose
fibers are crosslinked and modified. That is, the index uses that
the hydroxyl groups in the cellulose molecules are blocked by
crosslinking modification to lower the coefficient of moisture
absorption. The smaller the index, the larger the degree of
crosslinking modification, and the larger the index, the smaller
the degree of crosslinking modification. Generally, the
crosslinking index of unprocessed cotton and hemp is about 4 to
5.
where A is the coefficient of moisture absorption of the fiber
structure after crosslinking in an atmosphere of 30.degree. C. and
90% RH (%), and B is the coefficient of moisture absorption of the
fiber structure after crosslinking in an atmosphere of 20.degree.
C. and 65% RH (%).
If the crosslinking index is smaller than 1, the crosslinked
structure is formed excessively to lower the strength and
flexibility of the fabric, and though the fabric is good in shape
stability, it cannot be practically used. On the other hand, if the
crosslinking index is larger than 4, the crosslinking modification
of cellulose fibers is insufficient, and the required level of
shape stability such as crease resistance and shrinkage resistance
cannot be imparted. Considering the balance among the strength,
flexibility and shape stability of the fabric, it is preferable
that the crosslinking index is in a range of 2 to 3.5.
The nitrogen-containing polyfunctional compound refers to a
compound having nitrogen and two or more functional groups. The
compounds which can be used here include, for example,
dimethylolethyleneurea, methylated dimethyloluron,
dimetlylolpropyleneurea, dimethyloldihydroxyethyleneurea,
4-methoxy-5-dimethylpropyleneurea dimethylolation product,
methylated trimethylolmelamine, dimethylolalkyltriazones,
dimethylolurea, hexamethylolmelamine, tetramethylolacetylenediurea,
etc.
For adding any of these crosslinking agents to cellulose fibers,
any of various means can be applied. Particularly, the crosslinking
agent can be applied as a gas, or by padding, immersion, spraying,
printing, coating, gravure processing or foam processing, etc. When
the crosslinking agent is a cellulose reactive resin,
polycarboxylic acid or isocyanate, etc., padding can be preferably
used.
In the crosslinking modification of cellulose fibers, for the
purpose of promoting the reaction of the crosslinking agent, a
catalyst can also be preferably used together, and for example, an
organic acid, organic amine salt, or a metal salt such as magnesium
chloride, zinc nitrate, zinc borofluoride, magnesium nitrate or
zinc chloride, etc. can be used.
For crosslinking modification of cellulose fibers by a crosslinking
agent, any ordinary crosslinking modification method can be
applied. A pre-cure method in which a crosslinking agent is added
to a fiber structure formed as a fabric, followed by heat treatment
can be used, though this invention is not limited to the method. It
is preferable that the heat treatment temperature is 80 to
220.degree. C. A more preferable range is 120 to 200.degree. C.
The cellulose fibers heat-treated like this have the
nitrogen-containing polyfunctional compound combined with cellulose
molecules, to have antimicrobial property very high in industrial
washing durability, and shows a microbicidal activity value
(Standard Test Method: JIS L 1902) of larger than 0.
The synthetic fibers which can be used in this invention include
polyester fibers of polyethylene terephthalate, polypropylene
terephthalate, polybutylene terephthalate, etc., acrylic fibers,
polyamide fibers of nylon 6, nylon 66, etc. The fiber structure of
this invention can be yarns, woven fabric or nonwoven fabric, etc.
Among these synthetic fibers, polyester fibers can provide a fiber
structure most excellent in the industrial washing durability of
antimicrobial property.
The fiber structure of this invention must have the cellulose
fibers and the synthetic fibers mixed as mixed fibers, mix-spun
fibers, mixed woven fabric or mixed knitted fabric, etc. In
addition, wool, silk, etc. can also be mixed. For securing
effective shape stability, it is preferable that the cellulose
fibers are contained by 10 to 90 wt % based on the total weight of
fibers.
In this invention, the synthetic fibers contain an antimicrobial
agent with an inorganic value/organic value ratio of 0.3 to 1.4. A
preferable antimicrobial agent is a pyridine based antimicrobial
agent having a molecular weight of 200 to 700 and an average
particle size of 2 .mu.m or less.
A pyridine based antimicrobial agent strongly adheres to or is
exhausted and diffused into the synthetic fibers. It is considered
that if the antimicrobial agent is made closer to a disperse dye to
be exhausted and diffused into fibers, in three factors of
molecular weight, inorganic value/organic value ratio and average
particle size, it shows behavior similar to that of the disperse
dye. If these factors are not satisfied, the antimicrobial agent
does not strongly adhere or is not exhausted or diffused into the
synthetic fibers, and sufficient industrial washing durability
cannot be obtained.
If the molecular weight is less than 200, the washing durability
tends to be low though the antimicrobial agent adheres to or is
exhausted and diffused into the synthetic fibers. On the other
hand, if the molecular weight is more than 700, the antimicrobial
agent is unlikely to adhere to or to be exhausted into the
synthetic fibers. A preferable molecular weight range of the
antimicrobial agent is 300 to 500.
The "inorganic value/organic value ratio" in this invention is an
indicator contrived by Minoru Fujita, to express the polarity of
various organic compounds in view of organic concept [see Revised
Edition, Science of Chemical Experiments, Organic Chemistry, Kawade
shobo (1971)]. For the ratio, the organic value of one carbon (C)
atom is decided as 20, and the inorganic and organic values of
various polar groups are decided in reference to it, as shown in
Table 1. The inorganic value/organic value ratio refers to the
ratio of the sum of inorganic values to the sum of organic
values.
TABLE 1 Inorganic groups Value Inorganic groups Value Light metal
salt >500 >CO 65 Heavy metal salt, amine, ammonium salt
>400 --COOR, --P.dbd.P-- 60 --AsO.sub.3 H, --AsO.sub.2 H 300
>C.dbd.NH 50 --SO.sub.2 NHCO--, --N.dbd.N--NH.sub.2 260
--N.dbd.N-- 30 --SO.sub.3 H, --CONHCONHCO-- 250 >O 20 --SO.sub.2
NH--, --CONHCONH-- 240 Benzene nucleus (general aromatic single
nucleus) 15 --CONHCO--, --CSNH-- 230 Non-aromatic ring 10 .dbd.NOH
220 Triple bond 3 .dbd.N--NH-- 210 Double bond 2 --CONH-- 200
Organic and inorganic group Organic value Inorganic value --CSSH
180 >SO.sub.2 40 110 --CSOH, --COSH 160 --SCN 70 80 Anthracene
nucleus, phenanthrene nucleus 155 --NCS 70 75 --COOH 150 --NO.sub.2
70 70 Lactone 120 --CN 40 70 --CO--O--CO-- 110 --NO 50 50 --OH,
--As--O--As-- 100 --ONO.sub.2 60 40 --Hg(organic) 95 --NC 40 40
--COSR, --OSOR, --AS.dbd.AS-- 90 --NCO 30 30 Naphthalene nucleus 85
--I 60 20 --NH--NH--, --O--CO--O-- 80 --Br, --SH, --S-- 40 20
--NH.sub.2, --NHR, --NR.sub.2 70 --Cl, --P 20 20 Note: In the above
inorganic groups, each carbon atom is counted as an organic value
of 20. For SO.sub.2 group and those enumerated below it, the value
is already included in the organic value.
According to this organic concept, for example, the inorganic
value/organic value ratio of polyethylene terephthalate can be
calculated as 0.7. In this invention, attention is paid to the
affinity between synthetic fibers and an antimicrobial agent based
on the value calculated according to the organic concept, and an
antimicrobial agent with the inorganic value/organic value ratio
kept in a predetermined range is caused to adhere to or to be
exhausted and diffused into the synthetic fibers.
If the inorganic value/organic value ratio is less than 0.3, the
organic property is too strong, and on the contrary if more than
1.4, the inorganic property is too strong. In both the cases, the
antimicrobial agent is unlikely to adhere to or to be exhausted and
diffused into the synthetic fibers. It is preferable that the
inorganic value/organic value ratio is 0.35 to 1.3. A more
preferable range is 0.4 to 1.2.
For example, in the case of 2,3,5,6-tetrachloro-4-hydroxypyridine,
since it has one benzene nucleus, four --Cl groups, one --OH group
and one --NR.sub.2 group, the inorganic value is 265. On the other
hand, since it has five C (carbon) atoms and four --Cl groups, the
organic value is 180. Hence the inorganic value/organic value ratio
is 1.47. In the case of 2-pyridylthiol-1-oxide zinc, it exists as a
chelate complex, and in view of electronegativity, zinc and sulfur
are considered to be covalent-bonded. So, according to the
calculation, the compound has an inorganic value of 85 and an
organic value of 190, and an inorganic value/organic value ratio of
0.45. On the other hand, in the case of a further other pyridine
based antimicrobial agent, 2-pyridylthiol-1-oxide sodium, the
difference between sodium and sulfur in electronegativity is more
than 1.6, and their bond is an ionic bond. In this case, since
sodium acts as a light metal salt, it can be calculated that the
inorganic value is 585, that the organic value is 190, and that the
inorganic value/organic value ratio is 3.0. So, the compound is
poor in affinity to polyesters.
In this invention, among such antimicrobial agents, any one having
an average particle size of 2 .mu.m or less is used. If the average
particle size is more than 2 .mu.m, it is unlikely to adhere to or
to be exhausted into the synthetic fibers, and in addition, if it
is formed into a treating liquid, the particles settle to show a
tendency of poor liquid stability. It is preferable that the
average particle size of the antimicrobial agent is 1 .mu.m or
less.
The antimicrobial agents which can be used here include pyridine
compounds such as 2-chloro-6-trichloromethylpyridine,
2-chloro-4-trichloromethyl-6-methoxypyridine,
2-chloro-4-trichloromethyl-6-(2-furylmethoxy)pyridine,
di(4-chlorophenyl )pyridylmethanol,
2,3,5-trichloro-4-(n-propylsulfonyl)pyridine,
2-pyridylthiol-1-oxide zinc and di(2-pyridylthiol-1-oxide), etc.
Among them, especially 2-pyridylthiol-1-oxide zinc is preferable
since it is good in affinity to fibers, can adhere to or be
exhausted into fibers, hence good in washing durability and
effective against a wide range of microbes including MRSA.
Moreover, it is preferable that the fiber structure of this
invention has an microbicidal activity value of larger than 0 when
measured according to the microbiostatic evaluation method
(Standard Test Method: JIS L 1902) established by SEK (Japan
Association for the Functional Evaluation of Textiles) still after
50 times of industrial washing treatment at 80.degree. C. for 12
minutes using a wash liquor containing a surfactant. It is most
preferable that the microbicidal activity value is larger than 0
when measured according to the microbiostatic evaluation method
(Standard Test Method: JIS L 1902) established by SEK (New Function
Evaluation Council for Textile Products) still after 50 times of
industrial washing treatment at 85.degree. C. for 15 minutes using
a wash liquor containing a peroxide, strong alkali and
surfactant.
The wash liquor containing a peroxide, strong alkali and surfactant
is prepared, for example, by supplying 2 g/l of detergent "Zabu"
(registered trademark) produced by Kao Corp. as the surfactant, 3
cc/l of hydrogen peroxide water (35% for industrial use) as the
peroxide and 1.5 g/l of sodium percarbonate as the strong alkali,
into a drum dyeing machine filled with water at a bath ratio of
1:20. The wash liquor is then heated to 85.degree. C., and the
antimicrobial fiber structure of this invention and waste cloth are
supplied into it, to be washed for 15 minutes. The waste water is
discharged, and the fiber structure is dehydrated and washed with
overflowing water for 10 minutes, and dehydrated. This is one time
of washing. The washing is repeated 50 times, and the fiber
structure is dried using a tumbler dryer for 20 minutes, for
microbiostatic evaluation.
For letting the antimicrobial agent adhere to or be exhausted into
the synthetic fibers, the fiber structure is immersed in a solution
containing the antimicrobial agent in a jet dyeing machine, etc.,
and heated at atmospheric pressure or under pressurization at 90 to
160.degree. C. for 10 to 120 minutes, preferably at 120 to
135.degree. C. for 20 to 60 minutes. In this case, if necessary, a
disperse dye or disperse fluorescent whitening agent can also be
added to the solution.
In this method, it is preferable to effect dry heat treatment by a
tenter, etc. at 160 to 200.degree. C. for 15 seconds to 5 minutes,
more preferably at 170 to 190.degree. C. for 30 seconds to 2
minutes, after completion of the treatment in the solution. This
dry heat treatment allows the antimicrobial agent to be diffused
into the fibers annularly from the surfaces of the fibers, to allow
the washing durability to be improved without impairing the
antimicrobial property. These treatment conditions can be changed
to control such states as the adhesion of the antimicrobial agent
to the surfaces of fibers, the annular distribution in the fibers
and the diffusion in the fibers.
As another method, after the solution containing the antimicrobial
agent is caused to adhere to the fiber structure by padding or
spraying, etc., the fiber structure can be heat-treated by dry heat
treatment or wet heat treatment at 160 to 200.degree. C. for 30
seconds to 10 minutes, preferably 170 to 190.degree. C. for 1 to 5
minutes using a tenter, etc.
In view of cost and rationalization of processing, it is preferable
that after letting the crosslinking agent and the antimicrobial
agent adhere to the fiber structure by padding or spraying, etc.,
the fiber structure is heat-treated at 170 to 190.degree. C. for 30
seconds to 5 minutes, though the present invention is not limited
to this method.
In this invention, for the purpose of improving the softness of the
fabric, it is preferable to add a silicone based softening agent.
However, if a generally used silicone based softening agent is
used, or especially if an amino modified silicone based softening
agent mainly composed of an aminoalkyl group-containing
polysiloxane is used for treating the fabric, the treated fabric
has water repellency though it can have excellent softness and
softness durability, and so the treatment is unsuitable for
obtaining a cellulose fibers-containing fabric having shape
stability such as crease resistance and shrinkage resistance, and
also water absorbability as intended in this invention.
Therefore, in this invention, a silicone based softening agent
which gives a soft look and taste to the fabric without impairing
the water absorbability of the fabric is preferable. Particularly a
softening agent mainly consisting of an organopolysiloxane
containing both amino groups and polyoxyalkyl groups in one
molecule and a polyethylene polyamine higher fatty acid type amide
compound containing an amine or at least one group capable of
reacting with a hydroxyl group in one molecule is preferable.
The organopolysiloxane is not especially limited as far as it is an
organopolysiloxane containing both amino groups and polyoxyalkyl
groups in one molecule, i.e., an amino polyether modified silicone.
However, an organopolysiloxane having a viscosity of 100 to 100,000
cst at 25.degree. C. and an amino equivalent of 300 to 3000 is
preferable. Some or all of the amino groups of the amino polyether
modified silicone can be blocked by a compound reactive with the
amino groups, an organic acid or the anhydride or chloride, etc. of
an organic acid for prevention of yellowing.
The polyethylene polyamine higher fatty acid type amide compound
can be, for example, any of reaction products between any of
polyethylene polyamine higher fatty acid amides, urea condensation
products of polyethylene polyamine higher fatty acid amides and
imidazolinium salts of polyethylene polyamine higher fatty acid
type amide portions, and any of dicarboxylic acids, cyclic acid
anhydrides, diglycidyl ethers, diisocyanates, etc.
The polyethylene polyamines which can be used as a component of
these compounds include diethylenetriamine, triethylenetetramine,
tetraethylenepentamine, aminoethylethanolamine, etc. The higher
fatty acids which can be used here are generally those derived from
natural oils and fats such as palm oil, beef tallow, rapeseed oil,
rice bran coil and fish oil, but chemically synthesized higher
fatty acids can also be used. Among them, higher fatty acids having
an iodine value of 50 or less and 12 to 24 carbon atoms are
preferable. The dicarboxylic acids and cyclic acid anhydrides
include maleic acid, maleic anhydride, fumaric acid, malic acid,
succinic acid, succinic anhydride, tartaric acid, phthalic acid,
phthalic anhydride, etc. The diglycidyl ethers include ethylene
glycol diglycidyl ether, propylene glycol diglycidyl ether,
polyoxyalkylene glycol diglycidyl ether, neopentyl glycol
diglycidyl ether, 1,6-hexanediol diglycidyl ether, etc. The
diisocyanates include aromatic diisocyanates such as tolylene
diisocyanate, xylene diisocyanate and diphenylmethane diisocyanate,
aliphatic diisocyanates such as tetramethylene diisocyanate,
hexamethylene diisocyanate and lysine diisocyanate, etc.
The molar ratio of the polyethylene polyamine and the higher fatty
acid constituting the polyethylene polyamine higher fatty acid type
amide compound is usually 1:1.0.about.2.5, preferably
1:1.2.about.1.8.
The ratio by weight of the aminopolyether modified silicone and the
polyethylene polyamine higher fatty acid amide as the main
ingredients of the silicone based softening agent is
1:0.2.about.1.5, preferably 1:0.3.about.1.0. If the polyethylene
polyamine higher fatty acid amide is less than 0.2, sufficient
softness cannot be obtained, and if more than 1.5, the treated
fabric declines in water absorbability unpreferably.
It is preferable that the deposited amount of the silicone based
softening agent is 0.06 to 1.0 wt % based on the weight of the
fibers. If the deposited amount is less than 0.06 wt %, it is
difficult to impart sufficient softness and smoothness to the
fabric, and if more than 1.0 wt %, such defects as texture
dislocation are caused though the softness and smoothness are
improved.
In this invention, for the purpose of improving the water
absorbability of the fabric, it is preferable to add a hydrophilic
resin, particularly a hydrophilic polyester resin. As such a resin,
a resin mainly composed of a polyalkylene glycol-polyester block
copolymer can be preferably used.
The polyalkylene glycol referred to here has a main chain of
--C.sub.n H.sub.2n O-- (n=2.about.4) in the molecule, and
particularly can be polyethylene glycol, polypropylene glycol or a
block copolymer thereof, etc. It is preferable that the molecular
weight of the polyalkylene glycol is 300 to 4000. A more preferable
range is 1000 to 10000. If the molecular weight is less than 300,
the durability of deposition in the fibers tends to be
insufficient, and if more than 40000, the dispersibility tends to
decline.
The polyester which can be used for producing the block copolymer
of a polyalkylene glycol consists of an aromatic dicarboxylic acid
and an alkylene glycol. The aromatic dicarboxylic acids which can
be used here include, for example, terephthalic acid, lower alkyl
esters of and terephthalic acid, isophthalic acid and lower alkyl
esters of isophthalic acid. The alkylene glycols which can be used
here include, for example, ethylene glycol, propylene glycol,
butylene glycol, etc.
It is preferable that the deposited amount of the hydrophilic
polyester resin is 0.03 to 1.0 wt % based on the weight of the
fibers. If the deposited amount is less than 0.03 wt %, the effect
of adding the hydrophilic polyester resin is small, and if more
than 1.0 wt %, the fabric gives a slimy feeling while the color
fastness declines though the water absorbability of the fabric is
improved.
In this invention, a vinylsulfonic acid polymer can be preferably
fixed to the fiber structure, to make it hygroscopic.
The vinylsufonic acid polymers which can be used in this invention
include homopolymers and copolymers of vinylsulfonic acid monomers
such as 2-acrylamido-2-methylpropanesulfonic acid, styrenesulfonic
acid, isoprenesulfonic acid, allylsulfonic acid and
methallylsulfonic acid, and also copolymers consisting of any of
these vinylsulfonic acid monomers and a crosslinking agent. As the
crosslinking agent of the vinylsulfonic acid polymer, a
polyfunctional vinyl monomer which makes the produced polymer
three-dimensional can be preferably used. Furthermore, if a
vinylsulfonic acid polymer is crosslinked by a crosslinking agent,
high washing durability can be obtained.
Moreover, the sulfonate group ends of the vinylsulfonic acid
polymer can be substituted by at least one kind of metal ions
selected from Na.sup.+, Ni.sup.+, Cu.sup.2+, Zn.sup.2+, Mn.sup.2+,
Ag.sup.+ and Fe.sup.2+, for preventing that the cellulose fibers
are made brittle or discolored by an acid. Furthermore, in this
invention, it is preferable that the amount of the vinylsulfonic
acid polymer to be fixed is 1 to 20% owf in view of hygroscopicity,
durability and look & taste, and also in view of excellent
hygroscopicity and moisture retention.
In this invention, it is also preferable that the fiber structure
is made water-repellent by making a polyfluoroalkyl
group-containing acrylic copolymer, silicone resin and aminoplast
resin and/or polyfunctional block isocyanato group-containing
urethane resin deposited in the fiber structure.
The polyfluoroalkyl group-containing acrylic copolymers which can
be used here are not especially limited, and include, for example,
homopolymers of vinyl monomers having a polyfluoroalkenyl group
with 3 to 20 carbon atoms or a polyfluoroalkyl group, and
copolymers consisting of any of such vinyl monomers and another
vinyl monomer having neither polyfluoroalkenyl group nor
polyfluoroalkyl group.
The vinyl monomers having a polyfluoroalkenyl group or
polyfluoroalkyl group which can be used here include, for example,
CH.sub.2 =CHCOOCH.sub.2 C.sub.7 F.sub.15 CH.sub.2
=C(CH.sub.3)COOCH.sub.2 C.sub.6 F.sub.12 CF.sub.3 (CF.sub.3)
CH.sub.2 =CHCOO(CH.sub.2).sub.2 N(C.sub.3 H.sub.7)SO.sub.2 C.sub.8
F.sub.17 C.sub.6 F.sub.13 CH.sub.2 OH C.sub.8 F.sub.17 SO.sub.2
(C.sub.3 H.sub.7)CH.sub.2 CH.sub.2 OH C.sub.8 F.sub.17 SO.sub.2
(C.sub.3 H.sub.7)CH.sub.2 COOCNH(CH.sub.2).sub.6 NH(CH.sub.2
CN.sub.2 O).sub.11 CH.sub.3
The other vinyl monomers having neither polyfluoroalkenyl group nor
polyfluoroalkyl group include, for example, ethylene, vinyl
chloride, vinylidene chloride, acrylamide, styrene, benzyl
acrylate, vinyl alkyl ketone, maleic anhydride, isoprene, siloxane
and block isocyanates. Among them, an acrylic copolymer mainly
composed of a copolymer containing a block isocyanate as a vinyl
monomer is suitable. It is preferable that the polyfluoroalkyl
group-containing acrylic copolymer is contained by 0.01 to 10% owf
based on the amount of the fiber fabric. An especially preferable
range is 0.03 to 5% owf.
The aminoplast resins which can be used in this invention include,
for example, melamine resins such as trimethylolmelamine resin and
hexamethylolmelamine resin, urea resins such as
dimethylolpropyleneurea resin, dimethylolethyleneurea resin and
dimethylolhydroxyurea resin, uron resins such as dimethyloluron
resin. Among them, hexamethylolmelamine resin is suitable. It is
preferable that the amount of the aminoplast resin is 0.01 to 2 wt
% as the solid content based on the weight of the fiber fabric. An
especially preferable range is 0.02 to 1 wt %.
When an aminoplast resin is used, a generally used catalyst can
also be used. The catalysts which can be used here include
ammonium, aluminum and zinc salts of inorganic acids such as
phosphoric acid, sulfuric acid and nitric acid, and salts of
organic acids such as formic acid, acetic acid, acrylic acid and
succinic acid.
As the polyfunctional block isocyanato group-containing urethane
resin in this invention, any organic compound containing two or
more block isocyanato functional groups in the molecule can be used
without any limitation, and it can be a polyfunctional block
isocyanate urethane resin obtained by reaction with aphenol,
diethyl malonate, methyl ethyl ketone oxime or sodium bisulfite,
etc. to allow reproduction of active isocyanato groups by
dissociation when heated.
Especially preferable is a water dispersion of methyl ethyl
ketoxime of diphenylmethane diisocyanate or of methyl ethyl
ketoxime of trimethylolpropane tolylene diisocyanate adduct.
It is preferable that the amount of the polyfunctional block
isocyanate urethane resin is 0.01 to 4 wt % as the solid content
based on the weight of the fiber fabric. An especially preferable
range is 0.03 to 1 wt %.
Furthermore, a catalyst can also be used to promote the lowering of
the dissociation temperature of the polyfunctional block isocyanato
group-containing urethane resin, and dibutyltin dioleate,
dibutyltin stearate, stearyl zinc or an organic amine compound can
be preferably used as the catalyst.
In this invention, a photocatalyst semiconductor composed of a
compound oxide of titanium and silicon can be preferably fixed to
the fiber structure using at least one binder selected from alkyl
silicate resins, silicone resins and fluorine resins, to impart
deodorizability and odor impregnation preventability to the fiber
structure.
In this invention, the photocatalyst semiconductor has a nature of
oxidizing and decomposing organic substances by the strong
oxidizing power excited by ultraviolet light, and particularly can
be a semiconductor having a crystal structure called anatase,
rutile or brookite.
In this invention, attention is paid to the fact that such a
photocatalyst semiconductor has deodorizability, coloring matter
decomposing and removing capability (antifouling property) and
antimicrobial property (antibacterial and antifungal property).
Formaldehyde is generated after the cellulose fibers are
crosslinked and modified by a crosslinking agent such as
formaldehyde or cellulose reactive resin, to impart shape stability
such as crease resistance and shrinkage resistance to the cellulose
fibers, and also formaldehyde is liberated at the time or
crosslinking, to remain in the fabric. The photocatalyst
semiconductor is used to oxidize and decomposte such formaldehyde,
so that the fabric obtained may be excellent in crease resistance
and very small in the concentration of formalin produced to remain
as a result of decomposition of the crosslinking agent, preferably
as small as 20 ppm or less, and furthermore may have
deodorizability, antifouling property and microbicidal
capability.
The photocatalyst semiconductor of this invention removes the
tobacco smell and the body smell due to sweat, etc. in good
balance, which are difficult to remove by conventional techniques.
Furthermore, since it can oxidize and decompose such odors, it can
prevent the fabric from being impregnated with any odor as an
unprecedentedly very excellent effect. Moreover, since it can
decompose and remove coloring matters such as the tar of tobacco,
it can manifest an antifouling effect against coloring matters. In
addition, since the photocatalyst semiconductor of this invention
has microbicidal power against MRSA, Escherichia coli,
Staphylococcus aureus, etc., it can also manifest an effect in
antimicrobial and antifungal finishing.
If the photocatalyst semiconductor is too large in particle size or
too small in specific surface area, the rate of decomposing organic
substances, particularly bacteria tends to decline. As for the
deodorizing reaction, offensive odor components are adsorbed by the
photocatalyst semiconductor, and later decomposed by the oxidizing
power generated by the excitation of the photocatalyst
semiconductor caused by ultraviolet light. In this case, whether
offensive odor components can be adsorbed well or not greatly
affects the deodorizing efficiency. So, a photocatalyst
semiconductor with a primary particle size of 20 nm or less and a
specific surface area of 100 to 300 m.sup.2 /g can be preferably
used. If the amount of the photocatalyst semiconductor deposited in
the fiber structure is too small, the rate at which organic
substances such as offensive odor components are decomposed
declines not allowing a sufficient effect to be obtained. If too
large on the contrary, the fiber fabric is deteriorated by the
oxidation of the photocatalyst semiconductor and becomes hard in
taste and look unpractically, and furthermore, the fibers
themselves and binder, etc. are decomposed by the oxidative
decomposition of the photocatalyst semiconductor , to issue an
offensive odor disadvantageously. So, it is preferable that the
deposited amount of the photocatalyst semiconductor is 0.05 to 30
wt % based on the weight of the fiber structure. A more preferable
range is 0.05 to 20 wt %, and an especially preferable range is
0.08 to 10 wt %.
As the photocatalyst semiconductor of this invention, it is
preferable to use a compound oxide of titanium and silicon. As the
compound oxide, the compound oxide produced according to the method
described in Japanese Patent Publication (Kokoku) No. Hei5-55184
can be used. In general, a binary compound oxide of titanium and
silicon is known as a solid acid as described, for example, in
"Catalysts" (Vol 17. No. 3, Page 72, 1975), and shows remarkable
acidity which cannot be observed in the respective oxides
constituting the compound oxide, having a high surface area. That
is, the compound oxide of titanium and silicon is not a simple
mixture consisting of titanium oxide and silicon oxide, and when a
binary oxide of titanium and silicon is formed, it manifests
peculiar properties. Furthermore, the compound oxide has an
amorphous or almost amorphous fine structure if analyzed by X-ray
diffraction, and as for the ratio of titanium and silicon, it is
preferable that the compound oxide consists of 20 to 95 mol % of
titanium oxide and 5 to 80 mol % of silicon oxide. If the rate of
silicone oxide is larger than this range, the photocatalyst
activity of titanium oxide tends to be weak. So, it is preferable
to decide the optimum ratio for each purpose of use.
In this invention, to make any of various photocatalyst
semiconductors such as the compound oxide of titanium and silicon
deposited in the cellulose fibers-containing fabric, any of various
binders such as urethane resins, acrylic resins and cellulose
resins can be used. However, preferably, if at least one binder
selected from alkyl silicate resins, silicone resins and fluorine
resins is used, the decomposition, coloration and offensive odor
generation peculiar to organic resins by the oxidation of the
photocatalyst semiconductor can be prevented. In such a
combination, it is not necessary to form an intermediate layer of
an inorganic substance such as titanium peroxide between the fibers
and the binder containing the photocatalyst semiconductor, and the
photocatalyst semiconductor can be used to dramatically improve the
washing durability, taste & look, and also cost.
An alkyl silicate resin mainly consists of Si--O bond portions and
a straight chain or branched chain saturated alkyl group, and has
OH groups at both the ends characteristically. That is, it contains
a structure represented by the following formula.
In the above formula, R denotes a straight chain or branched chain
saturated alkyl group with 1 to 10 carbon atoms, and n is an
integer of 1 or more, preferably in a range of 1000 to 10000 for
enhancing the inorganic property.
The alkyl group is a straight chain or branched chain saturated
alkyl group such as methyl group, ethyl group, propyl group or
isopropyl group. The alkyl silicate resin used can also be one
alkyl silicate resin or a mixture consisting of two alkyl silicate
resins. The alkyl silicate resin has a feature that it easily
causes dehydration reaction in the presence of heat, to form a
polysiloxane film. The alkyl silicate resin is soluble in water,
and if the fiber structure is impregnated with an aqueous solution
of the alkyl silicate resin, mangled by a mangle, and treated at
200.degree. C. or lower, a thin film is formed on the surface of
each fiber. It is also possible to make the alkyl silicate resin
and the compound oxide of titanium and silicon directly deposited
on the surface of fiber structure.
A binder mixture consisting of a silicone resin and a fluorine
resin can also be deposited on the fiber structure. These binders
are, as described above, excellent in heat resistance, light
resistance and chemicals resistance, and also excellent in
durability against the oxidizing power of the photocatalyst
semiconductor.
As the silicone resin, any of condensation crosslinking type resins
belonging to silicone resins and silicone varnishes can be used.
Products obtained by condensing one or more condensation
crosslinking type resins such as tetraethoxysilane and
methyltrimethoxysilane can also be used. These resins have a
three-dimensional structure and are most excellent in heat
resistance and chemicals resistance among silicone resins. If a
silicone oxide sol obtained by hydrolyzing tetraisopropoxysilane or
tetraethoxysilane by a strong acid in an alcohol/water mixed
solvent, a vitreous film can be formed characteristically. The film
obtained by such a sol/gel method is close to an inorganic
substance and can be preferably used.
Furthermore, as the fluorine resin, a vinyl ether and/or vinyl
ester and a polymerizable fluoroolefin compound can be preferably
used since they have very excellent properties. For example,
polyvinyl fluoride, polyethylene tetrafluoride,
tetrafluoroethylene-perfluoroalkyl vinyl ester, vinyl
ester-fluoroolefin, etc. can be preferably used since they are less
decomposed and deteriorated.
The differences of these silicone resins and fluorine resins from
usually often used organic resins such as acrylic resins, urethane
resins and epoxy resins are that the former resins contain few
hydrocarbon groups likely to be decomposed by heat or chemicals'
action, and contain a few hydrocarbon groups such as methyl groups
or phenyl groups as the end groups or side chains since the
silicone resins are mainly composed of Si--O bonds while the
fluorine resins are mainly composed of F--C bonds.
To the binder, a coupling agent can be further added, to improve
the bonding strength between inorganic substances and organic
substances, thus allowing chemical bond strength to work among the
fibers, binder and photocatalyst semiconductor. As a result, the
washing durability can be enhanced.
As the binder, zeolite can also be added, to improve the capability
to adsorb odor components, and to increase the inorganic component
ratio in the structure. As a result, there is an effect of
inhibiting the decomposition by the photocatalyst. If zeolite
containing a precious metal such as gold, platinum, silver or
palladium preferably by 0.01 to 5 wt % is used, the antimicrobial
effect can be further enhanced.
In this invention, if the fiber structure is pre-treated by high
pressure water vapor and crosslinked and modified using a
crosslinking agent, the crease preventing effect higher than the
conventional level can be obtained, and the decline of strength
after completion of crosslinking modification which has been a
conventional problem can be prevented.
The high pressure water vapor referred to here is saturated water
vapor of high temperature. Particularly, high pressure saturated
water vapor with a temperature of 120 to 200.degree. C. and a
pressure of 2 to 16 kg/cm.sup.2 is preferable. If the temperature
is lower than 120.degree. C., the effect by this treatment is
insufficient, and if higher than 200.degree. C., such phenomena as
yellowing and embrittlement caused by heat are caused unpreferably.
The treatment time can be appropriately set in relation with the
treatment temperature. Usually it is preferable that the treatment
time is 30 seconds to 30 minutes. For the treatment, any pressure
vessel capable of with standing these conditions can be used, and
an ordinary autoclave can be used.
The fiber structure is excellent in the antimicrobial property with
industrial washing durability, and also in shape stability, and can
be preferably used in the form of a woven fabric or knitted fabric,
being suitable for such applications as dress shirts, uniforms,
inner socks, interior products and sports clothing.
EXAMPLES
The present invention is described below more particularly in
reference to examples.
In the following examples and comparative examples, the quality was
evaluated according to the following methods.
(1) Washing Method
A drum dyeing machine was used to wash using a wash liquor
containing 2 g/l of detergent "Zabu" (registered trademark)
produced by Kao Corp., 3 cc/l of hydrogen peroxide water (35% for
industrial use) and 1.5 g/l of sodium percarbonate at a bath ratio
of 1:20 at 85.+-.2.degree. C. for 15 minutes, and the waste water
was discharged. The sample fabric was dehydrated and washed with
overflowing water for 10 minutes, then being dried using a tumbler
dryer for 20 minutes. This was one time of washing.
(2) Antimicrobial Test Method
The Standard Test Method (JIS L 1902) was adopted, and a clinically
isolated MRSA strain was used. A bouillon suspension of said test
strain was injected into a sterilized sample fabric and cultured in
an enclosed container at 37.degree. C. for 18 hours. The plate
counts before and after culture were measured to obtain a plate
count increment/decrement as follows.
The log (A/C) at log (B/A)>1.5 was identified as a plate count
increment/decrement, hence as an microbicidal activity value. An
microbicidal activity value of larger than 0 was judged to be
acceptable.
In the above, A denotes the plate count obtained by inoculating a
fabric not containing any antimicrobial agent with the strain and
immediately recovering the dispersed strain; B denotes the plate
count obtained by inoculating a fabric not containing any
antimicrobial agent with the strain, culturing it for 18 hours, and
recovering the dispersed strain; and C denotes the plate count
obtained by inoculating a fabric containing an antimicrobial agent
with the strain, culturing for 18 hours and recovering the
dispersed strain.
(3) Evaluation of Crease Resistance
Judged based on the 5-stage replica method of AATCC 124-1984. Class
5 (good).about.Class 1 (poor)
(4) Washing Shrinkage Percentage
Measured according to JIS L 1042.
(5) Evaluation of Hygroscopicity (.DELTA.MR) .DELTA.MR
(%)=MR2-MR1
where MR1 refers to the hygroscopicity (%) measured after allowing
an absolutely dry sample to stand in 20.degree. C. 65% RH
atmosphere for 24 hours, which corresponds to an environment in a
wardrobe, i.e., an environment before wearing, and MR2 refers to
the hygroscopicity (%) measured after allowing an absolutely dry
sample to stand in 30.degree. C. 90% RH atmosphere for 24 hours,
which almost corresponds to an environment in the clothing involved
in any bodily exercise.
.DELTA.MR is obtained by subtracting the value of MR1 from the
value of MR2, and suggests how much perspiration in the clothing is
absorbed when a person wearing the clothing takes bodily exercise.
It can be said that a higher .DELTA.MR value suggests a more
comfortable condition. In general, it is said that the .DELTA.MR of
polyesters is 0%, that of nylons 2%, that of cotton 4%, and that of
wool 6%.
(6) Water Repellency
Evaluated according to JIS L 1092 (spray method). 100: No deposited
wetting on the surface. 90: Slight deposited wetting on the surface
80: Wetting at water dropping points on the surface 70: Partial
wetting on the entire surface 50: Wetting on the entire surface 0:
Full wetting on the surface
(7) Odor Impregnation Preventability
Twenty five microliters of 0.01% isovaleric acid aqueous solution
was taken by a micro-syringe and 5 .mu.l of it was dropped at 5
points in the central region of a 10 cm.times.10 cm piece of a
fabric; at one point at the center of the fabric and at four points
surrounding said one central point, as if to form five spots on a
side of a dice. This fabric was allowed to stand under a
fluorescent lamp for 3 hours, and smelled by 10 persons for sensory
evaluation. The odor in this case was evaluated according to the
following criterion, and the mean value was adopted. 5: Severe odor
4: Strong odor 3: Easily sensible odor 2: Discernible but feeble
odor 1: Slightly sensible odor 0: No odor
Example 1
A woven fabric (with an areal unit weight of 185 g/m.sup.2)was
prepared as a sample fabric by mixing polyethylene terephthalate
spun fibers and cotton fibers at 50:50 into yarns of 45 yarn number
count and using the yarns as warp threads and weft threads.
This woven fabric was immersed in a treating solution of the
following composition (1), padded at a squeeze rate of 80%,
preliminarily dried at 130.degree. C. for 90 seconds and
heat-treated at 180.degree. C. for 1 minute, to prepare a sample.
At this moment, the antimicrobial agent had been exhausted and
diffused into the fibers. The evaluation results are shown in Table
2.
(1) Composition
Crosslinking agent Dimethyloldihydroxyethyleneurea resin aqueous
solution (solid content 20%)
Catalyst Magnesium chloride
Antimicrobial agent 2-pyridylthiol-1-oxide zinc (inorganic
value/organic value ratio: 0.45, molecular weight: 317, average
particle size: 0.5 .mu.m) Aminosilicone resin with an amino
equivalent of 3000 g/mole (solid content 20%)
Hydrophilic polyester resin Polyethylene glycol (molecular weight
3000) copolymer emulsion (solid content 10%) consisting of 500
parts of dimethyl terephthalate and 400 parts of ethylene glycol
Even after industrial washing, the fabric showed good shape
stability and antimicrobial property.
Example 2
A woven fabric obtained by using 75-denier polyethylene
terephthalate yarns respectively consisting of 72 filaments and
cotton yarns of 45 yarn number count together at 50:50 was used as
a sample fabric. The woven fabric was treated as described for
Example 1 by a treating solution of the following composition (1),
immersed in a treating solution of the following composition (2),
mangled by a mangle at a squeezing rate of 40%, dried in a dryer at
120.degree. C. for 2 minutes, treated by a 100.degree. C. heating
steamer for 3 minutes and washed with hot water, to obtain a
sample. At this moment, the antimicrobial agent had been exhausted
and diffused into the fibers. The evaluation results are shown in
Table 2.
(2) Composition
Sodium 2-acrylamido-2-methylpropanesulfonate 160 g/l
N-methylolacrylamide 10 g/l Ammonium persulfate 3 g/l Monomer
represented by the following chemical formula 30 g/l where X
denotes a methyl group, and n denotes 23.
##STR2##
Even after industrial washing, the fabric showed good shape
stability and antimicrobial property, and even after 10 times of
household washing, the fabric showed good hygroscopicity.
Example 3
The woven fabric as used in Example 1 was used as a sample fabric
and immersed in a treating solution of the following composition
(3), padded at a squeezing rate of 80%, preliminarily dried at
130.degree. C. for 90 seconds and heat-treated at 180.degree. C.
for 1 minute, to prepare a sample. At this moment, the
antimicrobialagent had been exhausted and diffused into the fibers.
The evaluation results are shown in Table 2.
(3) Composition
Crosslinking agent Dimethyloldihydroxyethyleneurea resin aqueous
solution (solid content 20%)
Catalyst Magnesium chloride
Antimicrobial agent
2-chloro-4-trichloromethyl-6-(2-furylmethoxy)pyridine (inorganic
value/organic value ratio: 0.73, molecular weight: 329, average
particle size: 0.7 .mu.m)
Silicone resin Aminosilicone resin with an amino equivalent of 3000
g/mole (solid content 20%)
Hydrophilic polyester resin Polyethylene glycol (molecular weight
3000) copolymer emulsion (solid content 10%) consisting of 500
parts of dimethyl terephthalate and 400 parts of ethylene
glycol
Fluorine based water repellent Copolymer (solid content 30%)
obtained by copolymerization reaction of the following compounds
and distilled water
C.sub.12 F.sub.25 (CH.sub.2).sub.2 OCOCH.dbd.CH.sub.2 88 g CH.sub.3
(C.sub.2 H.sub.5)CNONCH(C.sub.6 H.sub.4)CH.sub.2 (C.sub.6
H.sub.4)NHCOO(CH.sub.2)CH.dbd.CH.sub.2 1 g Stearyl acrylate 9 g
Vinyl chloride 4 g Stearylmethylammonium chloride 2 g C.sub.12
H.sub.25 O(C.sub.2 H.sub.4 O).sub.12 H 2.4 g Acetone 60 g Distilled
water 415 g Amine based catalyst 0.8 g
Aminoplast resin Hexamethylolmelamine resin (solid content 80%)
Catalyst Organic amine compound
Polyfunctional block isocyanato group-containing urethane resin
Water dispersion (solid content 30%) of methyl ethyl ketoxime of
diphenylmethane diisocyanate
Catalyst Dibutyltin dioleate
Even after industrial washing, the fabric showed good shape
stability and antimicrobial property, and even after 10 times of
washing, it showed good water repellency.
Example 4
A broad woven fabric with an areal unit weight of 112 g/m.sup.2
consisting of 45% of polyester yarns of 45 yarn number count and
55% of cotton yarns respectively scoured and marcerized according
to conventional methods was used. The woven fabric was treated as
described for Example 1, immersed in a treating solution of the
following composition (4) obtained by using an aqueous dispersion
of a compound oxide of titanium and silicon (concentration 20%)
with an average particle size of 0.3 .mu.m obtained from a compound
oxide of titanium and silicon with an average primary particle size
of 7 nm and an average specific surface area of 150 m.sup.2 /g, as
a photocatalyst, padded at a squeezing rate of 80%, preliminarily
dried at 130.degree. C. for 90 seconds and heat-treated at
180.degree. C. for 1 minute, to prepare a sample. At this moment,
the antimicrobial agent had been exhausted and dispersed into the
fibers. The evaluation results are shown in Table 2.
(4) Composition
Alkyl silicate resin (concentration 20%) 1.0 wt % Silicone resin
(concentration 45%) 1.5 wt % Silane coupling agent (concentration
100%) 0.2 wt % Zeolite carrying a precious metal (concentration
20%) 0.3 wt % Compound oxide of titanium and silicon (concentration
20%) 1.0 wt %
Even after industrial washing, the fabric had good shape stability
and antimicrobial property, and also had good deodorizability and
odor permeation preventability.
Example 5
Three rolls (each about 25 yards) of the woven fabric used in
Example 4 were wound around a 110 cm wide 100 mm dia. bobbin, and
treated by high pressure water vapor in an autoclave at 180.degree.
C. at a pressure of 9.4 kg/cm.sup.2 for 3 minutes. The woven fabric
was immersed in a treating solution containing 70 g/l of
dimethyloldihydroxyethyleneurea resin aqueous solution (solid
content 20%) as a crosslinking agent and 10 g/l of magnesium
chloride as a catalyst, padded at a squeezing rate of 80%,
preliminarily dried at 100.degree. C. for 2 minutes and
heat-treated at 170.degree. C. for 1 minute. At this moment, the
antimicrobial agent had been exhausted and diffused into the
fibers. The evaluation results are shown in Table 2.
Even after industrial washing, the fabric had good shape stability
and antimicrobial property.
Comparative Example 1
A sample fabric as used in Example 1 was treated by a treating
solution of the following composition (5), to prepare a sample. The
evaluation results are shown in Table 2.
(5) Composition
Antimicrobial agent 2-pyridylthiol-1-oxide zinc
Silicone resin Aminosilicone resin with an amino equivalent of 3000
g/mole (solid content 20%)
Hydrophilic polyester resin Polyethylene glycol (molecular weight
3000) copolymer emulsion (solid content 10%) consisting of 500
parts of dimethyl terephthalate and 400 parts of ethylene
glycol
Comparative Example 2
A sample fabric as used in Example 2 was treated by a treating
solution of the following composition (6), to prepare a sample. At
this moment, the antimicrobial agent had not been exhausted into
the fibers. The evaluation results are shown in Table 2.
(6) Composition
Crosslinking agent Dimethyloldihydroxyethyleneurea resin aqueous
solution (solid content 20%)
Catalyst Magnesium chloride
Antimicrobial agent Methyl
6-(2-thiophenecarbonyl)-1H-2-benzimidazolecarbamate (inorganic
value/organic value ratio: 1.52, molecular weight: 302, average
particle size: 0.5 .mu.m)
Silicone resin Aminosilicone resin with an amino equivalent of 3000
g/mole (solid content 20%)
Hydrophilic polyester resin Polyethylene glycol (molecular weight
3000) copolymer emulsion (solid content 10%) consisting of 500
parts of dimethyl terephthalate and 400 parts of ethylene
glycol
In Comparative Example 1, since the crosslinking index did not
satisfy the condition of claim 1 because of no crosslinking agent
used, the shape stability was poor. In Comparative Example 2, since
the inorganic value/organic value ratio of the antimicrobial agent
did not satisfy the condition of claim 1, the antimicrobial
property after washing was poor.
TABLE 2 Example Example Example Example Example Comparative
Comparative 1 2 3 4 5 Example 1 Example 2 Crosslinking index 3.4
3.3 3.2 3.4 3.5 4.5 2.0 Crease resistance (class) 4 4 4 4 4-5 1-2
-- Washing shrinkage Warp 0.2 3.0 0.2 0.2 0.2 4.0 3.4 percentage
(%) Weft 0.1 2.8 0.1 0.1 0.1 3.0 3.0 Antimicrobial property KL-50
3.0 2.8 3.3 3.2 3.0 3.0 -0.2 (microbicidal activity value)
Hygroscopicity Before washing -- 4.0 -- -- -- -- -- (.DELTA.MR)
After washing -- 2.5 -- -- -- -- -- Water repellency Before washing
-- -- 100 -- -- -- -- After washing -- -- 70+ -- -- --
Deodorizability (marks) Before washing -- -- -- 0.5 -- -- --
(isovaleric acid odor) After washing -- -- -- 1.0 -- -- --
* * * * *